1. Field
The present invention relates generally to an improved data processing system and in particular to a method and apparatus for processing image data. Still more particularly, the present invention relates to a computer implemented method, apparatus, and computer usable program code for three dimensional tomographic image reconstruction of objects.
2. Background
Identifying targets or objects by their features of interest in a three dimensional space is a desirable objective for use in identifying unknown objects. Currently, synthetic aperture radar (SAR) is a form of coherent radar in which sophisticated post-processing of data obtained by this type of system is used to produce three dimensional radar images. Stereo synthetic aperture radar systems extract range information from the geometric disparity between two different views on the same point for a three dimensional object. With this type of system, a registration technique is needed to register that point on multiple images. In the presence of clutter and when the object is moving, an accurate registration becomes extremely challenging.
Another type of stereo aperture radar system is interferometric system aperture radar, which derives directly the relative height of a point of a three dimensional object from the interference pattern of radar returns received by two antennas that are separated vertically by a base. The ability of this type of system to resolve height information is determined by the size of the base between two antennas. The antenna base may affect deployment of this type of radar on small size airborne vehicles.
Laser imaging detection and range systems send out light beams to “paint” an object. These systems then measure the time-of-flight of return beams to reconstruct a distribution of reflective coefficients for a three dimensional object. One shortcoming of this type of system is that laser imaging detection and ranging systems are limited by weather conditions and air quality. Therefore, there remains a need in the art for a detection system that is less limited by weather conditions and air quality.